I've found a theme that I want to use on another site that I want to use on Forummotion. I created a new temporary theme and inputted the CSS into it. I uploaded all the images and changed the links in the CSS to match them. I then removed all the "default" images urls in the "Pictures" tab.

However, once I was done, when I previewed the forum it still looked the same, save for the header image.

I followed this tutorial quite closely, but it still doesn't seem to have changed. Is there any reason why this wouldn't work, or anything I can do to make it work?